A construction of the genetic map is based on the third law of genetics—law of linkage and crossing-over, i.e. a genetic map taking a genetic marker having a genetic polymorphism as a “sign”, and taking a genetic distance (a percentage of crossing-over and recombination between two sites in a meiotic event, 1% of a recombination rate is known as 1 cm) as a map distance. The construction of the genetic map has great implications for various species researches, which can elaborate genetic laws and characteristics of the species. Using this function, many genetic laws of a biological function related to human can be studied. For example, in the study of crops, the construction of the genetic map can enable us to acknowledge a genetic recombination rule of high-yield crops or anti-disease-related gene, which can give a guidance for breeding works to obtain a high-yield product with a strong patience; however for humanity itself, the construction of the genetic map can better enable us to study a certain genetic diseases, as well as give a guidance for eugenics.
However, the tradition methods of constructing the current genetic map cannot well applied to human beings. Because the construction of the genetic map is based on a statistical analysis of randomly allocating a homologous recombination event produced in meiosis to a progeny individual, a plenty of individuals of every progeny needs to be selected to study, however, the mammal lacks of a plenty of progenies for constructing a map, which directly restricts a process of constructing the human genetic map, since it is difficult to select such a large family to meet a randomness condition in statistics for study. N. ARNHEIM, H. LI et al. use a single sperm to construct a genetic map (Genetic mapping by single sperm typing, Animal Genetics 1991, 22, 105-115), which solves a problem of a sample selection, however, there is still a significant limitation. The method used herein can only amplify a part of known genes for subsequent analysis, which not only depends on primer effects, but also can do nothing regarding unknown genes and fragments which are not easy to amplify, thus, the genetic map obtained by such method is relatively one-sided and deficient.
A Next-Generation high-throughput sequencing technique represented by Illumina Solexa, ABI SOLiD and Roche 454, and a Third sequencing technique (i.e. a single molecule sequencing technique), mainly comprise: real single molecule sequencing technology of Helicos company, single molecule real time sequencing technology of Pacific Biosciences company, nanopore sequencing technology of Oxford Nanopore Technologies company, and et al., which have developed fast in the recent years and become important tools for genetics study.